A seller can open an Unpaid Item case after four days from item ending if the item was listed to sell on ebay.ca. (It may be sooner on ebay.com or ebay.co.uk.) Are you the buyer or the seller? Either way, if you are planning to step out for a few days, it might be advisable to let your trading partner know so that they aren't wondering if you are Missing in Action. Just a thought.